Automatic fire extinguisher



y 12, 1954 H. c. PELTIER 3,132,695

AUTOMATIC FIRE EXTINGUISHER Filed July 31, 1962 INVENTOR. f/t'lvey C- 106L775? United S te Pat n 3,132,695 AUTOMATIC FIRE EXTINGUISHER Henry C. Peltier, Hackensacir, N.J., assignor to Astrotec, Ina, Garfield, N..l., a corporation of New Jersey Filed July 31, 1962, Ser. No. 213,636 16 Claims. (Cl. 169-26) This invention relates to an automatic fire extinguisher, and, more particularly, is concerned with an automatic fire extinguisher of the flammable trigger type.

It is an object of my invention to provide a new and improved fire extinguishing device of the flammable trigger type which is particularly suited for use with natural Christmas trees in the home of virtue of its singularly quick and sensitive response to flame and which, at the same time, may be so decorated as to be inconspicuous while in use.

It is another object of my invention to provide a new and improved fire extinguisher of the character described which is of simple and inexpensive design, of easy manufacture, is durable and rugged in construction, and is not prone to be put into operation by an accidental contact.

It is another object of my invention to provide a new and improved fire extinguisher of the character described which is reliable in operation and which when actuated Will discharge a spray of a fire extinguishing medium to control or quench a nearby fire.

An important advantage of my novel fire extinguisher is its speed of response. The prior art in the field of automatic home-usage type fire extinguishers reveals that these mechanism are usually actuated byheat sensitive triggers. Such triggers commonly utilize a low melting alloy fusing from 100 to 180 F. The fusing of the low melting material may unblock an orifice or release a frangible container from its tree hanger, causing it to drop and shatter.

In contrast to the prior art, my invention has its novelty in its blocking of an orifice in an internally pressurized container by means of a flame sensitive trigger so that when the trigger is licked by flame it will kindle and then burn rapidly causing the trigger to disintegrate and lose its strength and thus speedily permit the orifice to be opened by the pressure of the flame quenching medium in the container, without waiting for the trigger to be burned through.

It is noted that heat sensitive fire extinguishers react slowly to a change in temperature since the fire extinguisher body and surrounding mechanism act as a heat sink tending to keep the fusible trigger below its fusing temperature. Thus, even when exposed to open flame the triggering mechanism may take up to thirty seconds of exposure to high temperature for the fusible trigger to soften sufliciently to actuate the mechanism; with a highly combustible substance such as aChristmas tree and its decorative ornaments, this time lapse may be more than enough for the fire to get out of control and cause a -the trigger will allow discharge of the extinguishing medium.

This and various other objects and advantages of my invention will become apparent to the reader in the following description.

My invention accordingly consists in the features of construction, combinations of elements and arrangement 3,132,695 Patented May 12, 1964 FCC of parts which will be exemplified in the device hereinafter described and of which the scope of application will be indicated in the appended claims.

In the accompanying drawings in which is shown one of the various possible embodiments of my invention,

FIG. 1 is an elevational view of a Christmas tree with my automatic fire extinguisher positioned at the top of the tree, having its optional flame-conducting tape hanging down through the tree;

FIG. 2 is a close-up perspective view of my automatic fire extinguisher shown hanging from a limb of the Christmas tree and further showing its flame-conducting tape depending from its flammable trigger;

FIG. 3 is a vertical central sectional view through my automatic fire extinguisher; and

FIG. 4 is a fragmentary view similar to FIG. 3 of the lower portion of the extinguisher, showing the discharge of the fire-extinguishing medium after the trigger mechanism has been actuated, that is, the highly flammable trigger has burned allowing the conical seal to be ejected from the discharge orifice.

In general I accomplish my invention by providing a container filled with a fire extinguishing medium under pressure. The container includes a discharge orifice which is closed by a highly flammable trigger having an e1on gated exposed portion (external to the container) so that when flame licks at the exposed portion, the trigger will both burn and disintegrate so as to free the pressurized extinguishing medium for egress through the orifice. In its preferred form the highly flammable trigger is a screw having its shank threaded in a bracket attached to the container and its tip pressing firmly against a conical seal blocking the discharge orifice, the screw being of such material as to ignite quickly and fail with extreme rapidity upon kindling.

Referring now in detail to the drawings, the reference numeral 10 denotes a fire extinguishing medium. A useful medium for this purpose is carbon tetrachloride which is easily volatilized and forms a heavy non-combustive vapor, thereby displacing air and smothering the fire. Similar valuable media are chlorobromomethane and perchloroethylene.

A propellant 12 is used to facilitate the rapid pressurized discharge of the fire extinguishing medium. 25 p.s.i.a. is found to be an adequate pressure to expel the medium rapidly While, by means of the discharge orifice, providing a blasting eflect by breaking up the medium into a spray. A good propellant is dichlorotetrafluoroethane, having a relatively high boiling point, low freezing point, being non-flammable, and, at household temperatures, generating a pressure in the range of 25 p.s.i.a.

The fire extinguishing medium and propellant are held within a container 14, formed of such material, e.g. sheet aluminum, as Will resist any corrosive effects of the medium and propellant. The container may be formed in any appropriate shape for decorative, structural or other reasons, the same not being a determinative factor of my invention. The container may be suitably decorated on its outer surface to emulate a decorative ornament.

As shown, the container 14 consists of tWo hemispheres 16, 18 mechanically joined at their peripheriesZil by appropriate means, e.g. a mechanically interlocking joint, to constitute a fiuid' tight seal. A hook 22 is attached to the container 14 at the top of the upper hemisphere 16, by being secured to a plug 24 which is used to close a charge hole in the container. The'hook allows the extinguisher to be mounted in an appropriate protective position as, for example, near the top of a Christmas tree, over a furnace, to a ceiling in a factory or behind a kitchen range. The plug is suitably fixed in place, as by soldering, after the container has been charged with an extinguishing medium and a propellant.

The container is provided with a small discharge orifice 26 which has been pierced and die-formed to eflectuate the shape of a frustum of a cone (see FIGS. 3 and 4) with its apex extending inwardly. It will be appreciated that by using a discharge orifice of this design, to wit, a small discharge hole leading into a wide mouthed funnel, the extinguisher will discharge its pressurized medium in a heavy mist-like spray. This will allow maximum utilization of the fire exinguishing medium, so as to rapidly bring the fire under control. The propellant in the container will thus blast the medium out through the orifice, breaking the spray into fine particles and spreading a heavy mist to extinguish a nearby fire.

Extending into and held in the orifice 26 is a conical seal 28 which is designed to mate with and normally close the discharge orifice. A suitable material for this seal is polychlorotrifluoroethylene (Teflon) a polymer which is highly stable and generally inert to fire extinguishing media. This plastic is strong, tough, readily formed into desired shapes and exhibits a sufficient degree of flexibility to allow it to fit snugly into the discharge orifice under pressure.

A highly flammable element, Le. a screw 30, serves as a flame sensitive trigger for the fire extinguisher. The screw 30 is elongated along an axis that extends radially away from the container 14. The screw has one end proximate to the container which end blocks the discharge orifice 2 6 and another distant end extending away from the container. The latter end is, by virtue of its exposed position, readily accessible to the flames of a destructive fire. Means attached to the container compresses the flammable element so that the element will quickly fail upon kindling. Said means firmly engages or grips the element at a point distant from its blocking end.

T this end, the blocking end or tip of the highly flammable screw 30 fits into a depression in the base of the conical seal 28. The shank of the screw is threaded in its middle portion into a hole in the central section of a bracket 32 the ends of which are attached as by solder to the lower hemisphere 18. It is seen that by appropriately turning the screw 36 by means of its slotted head 34, the screw can be raised or lowered relative to the bracket so as to firmly force the conical seal 28 into firm sealing engagement with the discharge orifice 26. The screw 30 includes a constricted neck intermediate its blocking end and the point along its length, distant from the blocking end, at which it is threadedly engaged by the bracket 32. Although the trigger mechanism is shown in its preferred form, alternative expedients are to have the conical seal rotatably attached to the tip of the flammable screw, or to have the seal and the screw formed as a unitary structure from one piece of material.

In its preferred form, the highly flammable screw 30 is made from cellulose nitrate or from Celluloid, a wellknown thermoplastic constituting a mixture of nitrocellulose and camphor. Both said materials have high strength, toughness, dimensional stability, are easily fabricated and are highly flammable.

As an ancillary feature, a highly flammable tape 36 depends from the flammable screw 30 at a point distant from the blocking end. The tape may be several feet long so that when placed for example in a Christmas tree, it will have sufficient length to run from the fire extinguisher body located near the top of the tree down through the length of the tree to the floor or base supporting the tree. The tape is made from thin pliable material ribbon which is highly flammable, preferably a cellulosenitrate plastic or Celluloid.

From the aforegoing description, it will be realized that the trigger mechanism has its greatest novelty in the speed with which it reacts to flame exposure. As seen from the accompanying drawings, the highly flammable screw is so positioned as to have an elongated exposed portion readily accessible to flame. Thus, when the screw is kindled, by virtue of its highly flammable composition and exposed location, it ignites quickly and burns and disintegrates and so unblocks the orifice by releasing the orifice seal. The screw will speedily weaken and decompose at its constricted neck. When the screw is made of a cellulose nitrate plastic, which burns and disintegrates with great rapidity upon application of flame, the propellant in the container behind the fire extinguishing medium blows out the seal and thereafter spreads a fire quenching blanket to control any impending calamity.

It is further seen that the screw, while acting as a flame sensitive trigger, also acts to hold the conical seal in place. Thus the screw is under compression from two separate active forces: one, from the elfect of the screw being tightened in the bracket against the seal to close the orifice; secondly, the force of the propellant pressing down on the seal, this force being transmitted in compression against the screw. Such compression on the screw greatly aids the effectiveness of the instant invention, since this force will cause the screw to fail quickly when flame has kindled the screw.

The combination of these two factors, the highly flammable character of the screw, and the compression in which the screw is held, make the flammable trigger mechanism both highly sensitive and quickly responsive to the presence of flame, allowing the extinguisher to discharge and control any conflagration.

The ancillary feature of my extinguisher, is. the utilization of a highly flammable tape of substantial length to aid in conducting any outbreak of fire directly to the screw enlarges the area of effectiveness of the extinguisher. Being itself highly sensitive to flame, the tape conducts a flame very quickly along its length to the flame sensitive screw, allowing the extinguisher to discharge. Thus long before the flame has reached the surrounding height of the extinguisher, even while the temperature around the extinguisher is still normal room temperature, the tape will quickly conduct a flame from a still small fire to the screw and allow discharge.

It thus will be seen that there is provided a device which achieves the several objects of my invention, and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment set forth, it is to be understood that all matter herein described or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, 1 claim as new and desire to secure by Letters Patent,

1. A fire extinguisher comprising a container witha discharge orifice, a pressurized fire extinguishing medium within the container, a bracket attached and external to the container presenting a threaded hole aligned with the orifice, and a highly flammable screw with its shaft threaded through said hole, said screw having a portion blocking said orifice and an elongated exposed portion extending away from the container so that said screw is readily accessible to flame and will disintegrate upon kindling whereby to unblock the orifice, said screw being held by said bracket under compression against the ori fice so that said screw will quickly fail upon kindling.

2. A fire extinguisher comprising a container with a frusto-conical inwardly converging discharge orifice, a pressurized fire extinguishing medium within the container, an elongated bracket external to the container presenting a threaded hole aligned with the orifice in its middle section and attached by its end sections to the container, a highly flammable screw longitudinally oriented towards the orifice with its middle portion consti tuting a shaft threaded through the hole, said screw having a tip extending inwardly towards said orifice and an elongated exposed portion extending away from the container, an inwardly converging conical seal made of a tough flexible material interposed between the tipof the screw and the orifice, so as to tightly block said orifice, said screw being readily accessible to flame so that it will disintegrate upon kindling whereby to unblock the orifice, said screw being held by said bracket under compression against the conical seal so that said screw will quickly fail upon kindling.

3. A fire extinguisher as set forth in claim 2, wherein a highly flammable tape depends from the exposed portion of said screw.

4. A fire extinguisher as set forth in claim 2 wherein a highly flammable tape composed of cellulose nitrate depends from the exposed portion of said screw.

5. A fire extinguisher comprising a container having a discharge orifice, a fire extinguisher medium within the container, a propellant Within the container holding the fire extinguishing medium under expulsive pressure, a highly flammable rigid element elongated along an axis and having an end blocking said orifice and an exposed end extending away from the container and thereby readily accessible to flame, and means attached to the container and compressing the flammable element along its axis, so that the element will quickly fail upon kindling, and forcing the blocking end against the orifice so as to seal the orifice against the expulsive pressure of the propellant.

6. A fire extinguisher as set forth in claim 5 wherein the element compressing means firmly engages the element at a point distant from its blocking end.

7. A fire extinguisher as set forth in claim 6 wherein the element has a constricted neck intermediate its block ing end and the point at which it is engaged by the compressing means.

8. A fire extinguisher as set forth in claim 5 wherein the compressing means threadedly meshes with an intermediate portion of the element, said portion being distant from the blocking end.

9. A fire extinguisher as set forth in claim 5 wherein a highly flammable tape depends from a portion of the element distant from the blocking end.

10. A fire extinguisher as set forth in claim 5 wherein a flexible seal is interposed between the blocking end of the element and the discharge orifice.

References Cited in the file of this patent UNITED STATES PATENTS 624,611 Banks May 9, 1899 I 1,208,549 Haller Dec. 12, 1916 1,348,565 Jenkins Aug. 3, 1920 2,723,722 Hicks Nov. 15, 1955 FOREIGN PATENTS 208,072 Great Britain Dec. 13, 1923 

1. A FIRE EXTINGUISHER COMPRISING A CONTAINER WITH A DISCHARGE ORIFICE, A PRESSURIZED FIRE EXTINGUISHING MEDIUM WITHIN THE CONTAINER, A BRACKET ATTACHED AND EXTERNAL TO THE CONTAINER PRESENTING A THREADED HOLE ALIGNED WITH THE ORIFICE, AND A HIGHLY FLAMMABLE SCREW WITH ITS SHAFT THREADED THROUGH SAID HOLE, SAID SCREW HAVING A PORTION BLOCKING SAID ORIFICE AND AN ELONGATED EXPOSED PORTION EXTENDING AWAY FROM THE CONTAINER SO THAT SAID SCREW IS READILY ACCESSIBLE TO FLAME AND WILL DISINTEGRATE UPON KINDLING WHEREBY TO UNBLOCK THE ORIFICE, SAID SCREW BEING HELD BY SAID BRACKET UNDER COMPRESSION AGAINST THE ORIFICE SO THAT SAID SCREW WILL QUICKLY FAIL UPON KINDLING. 